Snoring is a common sleep disturbance, affecting both sexes and persons of all ages. Snoring is more often observed in men but is also highly prevalent in pregnant women. Snoring is often a symptom of obstructive sleep apnea (OSA), a disorder having serious comorbid symptoms. Upper airway resistance is a symptom that is often part of the continuum of OSA. OSA is characterized by repeated arousals from sleep. Symptoms of OSA, in fact, can be found in non-snorers. Edentulous people having old (worn down) dentures or people sleeping without their full denture also commonly snore and have OSA. Snorers, including pregnant women, can be screened for sleep breathing disorders. Such disorders can be treated using methods that are low cost, benign, non-invasive, drug-free and comfortable.
By the third trimester of pregnancy, 97% of women report sleep disturbances. Sharma S., Franco R., Sleep and its Disorders in Pregnancy, Wisconsin Medical Journal, 2004, 103(5) 48-52. It has been reported that as high as 46% of pregnant women snore in the third trimester. Sullivan C., Edwards N., Sleep-Disordered Breathing in Pregnancy in Randerath W J, Sanner B M, Somers V K (eds): Sleep Apnea, Prog Respir Res. Basel, Karger, 2006, vol 35, pp 224-237. “Pregnancy Associated Sleep Disorders” is now recognized as a distinct clinical entity in the International Classification of Sleep Disorders Manual (ICSD, DSM IV). American Academy of Sleep Medicine, International classification of sleep disorders, 2nd ed.: Diagnosis and coding manual, Westchester, IL: American Academy of SleepMedicine; 2005. 148-152. The spectrum of sleep disturbances in pregnant women ranges from increased incidence of insomnia, nocturnal awakening, nocturia, parasomnias (especially restless leg syndrome), to snoring and OSA. Sahota P. K., Jain S. S., Dhand R., Sleep Disorders In Pregnancy, Sleep and Respiratory Neurobiology, 2003; 9(6) 477-483.
It is generally agreed that pregnant women snore more than those who are not pregnant. In fact, a study reported frequent loud snoring in 14% of the pregnant women vs. 4% in the group of non-pregnant women. Loube D. I., Poceta S., Morales M. C., Peacock M. D., Mitler M. M., Self-Reported Snoring In Pregnancy: Association With Fetal Outcome, Chest, 1996; 109:885-89. Snoring may be a sign of pregnancy-induced hypertension. Franklin K. A., Holmgren P. A., Jonsson F., Poromaa N., Stenlund H., Svanborg E., Snoring, Pregnancy-Induced Hypertension, And Growth Retardation Of The Fetus, Chest, 2000 117:137-141.
Sleep disordered breathing is significantly more prevalent in obese pregnant women than pregnant women based on what is considered normal weight. Maasilta P., Bachour A., Teramo K., Polo O., Laitnen L. A., Sleep-Related Disordered Breathing During Pregnancy In Obese Women, Chest. 2001; 120(5):1448-1454. With the ongoing epidemic of obesity in the general population, obese pregnant woman may become the norm (the most common patient type).
A study has revealed that snoring pregnant women had a 2-fold greater incidence of hypertension, preeclampsia, intrauterine growth restriction and lower Apgar scores at birth. Franklin K. A., Holmgren P. A., Jonsson F., Poromaa N., Stenlund H., Svanborg E., Snoring, Pregnancy-Induced Hypertension, And Growth Retardation Of The Fetus, Chest, 2000 117:137-141. Pregnancy may precipitate or worsen OSA. Kowall J., Clark G., Nino-Murcia G., Powell N., Precipitation Of Obstructive Sleep Apnea During Pregnancy, Obstet Gynecol. 1989; 74: 453-455. OSA may also be a cause of fetal compromise. Sahin F. K., Gulengal K., Cosar E., Saylan F., Fidan F., Yilmazer M., Unlu M., Obstructive Sleep Apnea In Pregnancy And Fetal Outcome, Obste & Gyne Survey, 2008(5):292-293.
It is during the third trimester of pregnancy that these respiratory changes during sleep markedly increase the incidence and severity of sleep disordered breathing Edwards N., Middleton P. G., Blyton D. M., Sullivan C. E., Sleep Disordered Breathing And Pregnancy, Thorax, 2002(57):555-558. There is a 20% reduction in functional residual capacity and maternal oxygenation is decreased. Weinberger S. E., Weiss S. T., Cohen W. R., et al. State Of The Art: Pregnancy And The Lung, Am Rev Resp Dis; 1980; 121:559-581. Increased airway collapsibility during tidal ventilation increases susceptibility to snoring and OSA. Remmers J. E., deGroot W. J., Sauerland E. K., Anch A. M., Pathogenesis Of Upper Airway Occlusion During Sleep, J. Appl. Physiol. 1978; 44:931-938. This effect is exacerbated in the supine position. Edwards N., Middleton P. G., Blyton D. M., Sullivan C. E., Sleep Disordered Breathing and Pregnancy, Thorax, 2002(57):555-558.42% of pregnant women at 36 weeks gestation reported chronic nasal congestion and rhinitis. Bende M., Gredmark T., Nasal Stuffiness During Pregnancy, Laryngoscope 1999; 109:1108-1110.
Snoring alone is not a good marker for OSA in pregnant women. Snoring alone however may decrease the overall sleep quality of the mother-to-be and be a serious detriment to good sleep quality of the sleep partner. The combination of snoring and witnessed apneas provides a more reliable diagnostic screening tool for OSA.
In light of the above, it is desirable that pregnant women be screened for sleep disordered breathing. However, a full night polysomnographic evaluation can be onerous and unduly burdensome for a woman in her third trimester. Ambulatory home polysomnographic testing is an easy and benign alternative to a night totally wired up in a sleep lab, but does not have equivalent diagnostic accuracy.
OSA related to pregnancy appears to be self-limiting to the third trimester. The snoring and OSA usually discontinue with delivery of the baby and subsequent weight loss.
Existing treatments include intraoral mouthpieces and Continuous Positive Airway Pressure (CPAP) devices. However, known intraoral mouthpieces can be bulky, may cause discomfort, are generally more expensive and usually need fitting by a dentist. Also, CPAP requires attachment to devices, thereby inhibiting frequent positional changes during sleep. Pregnant women, having a difficult time finding a comfortable position, shift around often during sleep. Pregnant women also have enough hormonal, postural and psychological burdens to deal with that CPAP usually becomes an intolerable alternative.
In light of the foregoing, there is a need for an improved snoring treatment that can provide improved comfort.